<div style="display: flex; justify-content: left">
    <form class="example-full-width">
        <mat-form-field class="example-full-width">
            <mat-label>业务类型:{{fileYwlx}}</mat-label>
            <input type="text" aria-label="Number" matInput
                (input)="filterChanged($event.target.value)" [matAutocomplete]="auto">
            <mat-autocomplete autoActiveFirstOption #auto="matAutocomplete" (opened)="loadData()">
                <mat-option disabled>选择所属业务类型</mat-option>
                <mat-tree [dataSource]="dataSource" [treeControl]="treeControl">
                    <mat-tree-node *matTreeNodeDef="let node" matTreeNodeToggle matTreeNodePadding>
                        <button mat-icon-button disabled></button>                        
                        <mat-checkbox class="checklist-leaf-node" 
                            [checked]="checklistSelection.isSelected(node)"
                            [disabled]="disabledNode(node)"
                            (change)="checkboxChange(node)">{{node.item}}
                        </mat-checkbox>
                    </mat-tree-node>

                    <mat-tree-node *matTreeNodeDef="let node; when: hasChild" matTreeNodePadding>
                        <button mat-icon-button matTreeNodeToggle [attr.aria-label]="'toggle ' + node.filename">
                            <mat-icon class="mat-icon-rtl-mirror">
                                {{treeControl.isExpanded(node) ? 'expand_more' : 'chevron_right'}}
                            </mat-icon>
                        </button>
                        <!-- [checked]="descendantsAllSelected(node)"
                            [indeterminate]="descendantsPartiallySelected(node)" -->
                        <mat-checkbox 
                            [checked]="checklistSelection.isSelected(node)"
                            [disabled]="disabledNode(node)"
                            (change)="checkboxChange(node)">
                            {{node.item}}
                        </mat-checkbox>
                    </mat-tree-node>
                </mat-tree>
            </mat-autocomplete>
        </mat-form-field>
    </form>
</div>